1. Field of the Invention
This invention relates generally to a type of lightweight, pilot-carrying aircraft, ultralights, which do not use motors or propellers. The new control system provides additional means to control those ultralights that receive their lift from an inflatable ram-air flexible airfoil wing, particularly the paraglider.
2. Description of Related Art
Foot launched, non-motorized flying apparatuses include hang gliders, paragliders and hybrids of the hang glider and paraglider. Hybrids and hang gliders represent a distinctly different field than paragliders because their rigid frames and other rigid members put them very much closer to the more common aircraft which use rigid frame members.
2.A. FOUR PARAGLIDER AREAS
The three basic areas of current art paragliders are illustrated in schematic form in FIGS. 1, 2 and 3, i.e.: the harness area; the wing suspensory elements, risers, etc., and brake system for wing control; and the wing (100) itself.
A fourth area is sometimes chosen by more advanced pilots depending upon the paraglider model. Specifically, some pilots have chosen a model which can have a device that involves the legs. This device is commonly known as the speed stirrup system (130,131,132,135,136). Another area, not physically related to the legs, but functionally related to the speed stirrup system, is the trim tab system (141,144,145,149) located on the D riser (107d).
Referring to FIGS. 1 through 3, the first area, the harness (112) area, holds the pilot seated on a seat board (115). This area includes the elements up to the main carabiner quick link (110) on each side.
The pilot/harness is suspended from the second area by the elements of the wing suspensory parts (108, 106, 106a, 107a-d, 109, 110). As shown in FIG. 4, the main carabiner quicklink (110) is looped by a main carabiner riser complex (108a). This main carabiner riser complex is the joining together of the 4 risers, which are synthetic straps about 15/16 inches wide and 3/32 inches thick, that suspend the entire weight of pilot and harness. As seen in FIGS. 1, 3, and 4, the main carabiner riser complex (108a) continues on usually as a lower riser complex (108b) of four riser straps (107a-d): A riser, B riser, C riser and D riser. In the lower riser complex (108b) area these 4 straps are intricately interrelated. FIG. 4 shows one variation, but at a distance, such as in FIG. 3, this area of lower riser complex (108b) resembles a loop. In the upper riser complex (108c), these straps are more clearly independent. The upper ends of the risers (107a-d) are attached onto carabiner quick links (109). The carabiner quick links (109) are in turn attached to 5 separate lines (106). These lines (106) are attached in turn to supplemental suspension lines (106a), which in turn attach to approximately 150 places on the wing lower surface (104) of an inflatable, completely flexible cloth-like wing (100).
The speed stirrup system (150) including the Pulley (135), cord (131), etc. and trim tab system (149 including 141,145,144, etc.) are not on all paragliders. Both systems attach on the lower riser complex (108b); however the speed system (150) attaches to the front most riser. The trim tab system (149) attaches to the rear most riser, which is the D riser (107d) in this model. These two add on systems are discussed below.
Spatially related to second area of the paraglider is the wing control brake system (120, 121, 122). Along the wing trailing edge (102) of the wing (100) there are about 20 attachments which join into a brake line (121) leading to each of the pilot's hands. This brake line (121) serves no pilot suspension function and the brake line (121) is attached to the soft brake loop (120) which the pilot holds. The brake loops (120) are the control means the pilot has for the crucial task of helping the wing (100) to remain filled with air. Actually, proper brake loop (120) positioning and movement are critical for landing, turning and safety, and indeed for all flight activities.
The third area is the wing (100). Air comes in at the wing's (100) leading edge (101) through open window areas (105) and the air passing in separates the upper surface (103) from the lower surface (104). The wing (100) is constructed in such a way to then create an airfoil that flies. If the wing deflates, the pilot falls to his death.
Over the past 10 years the changing design of the wings (100) of paragliders now permits unlimited hours of soaring thousands of feet above the ground.
Experts and inventors in the field of paragliders and hang gliders have long conceptualized the hang glider and paraglider aircraft as distinct from aircraft involving propellers or motors. Critical to the satisfaction of the pilot is the sense of maximally pure and natural flying with the winds.
This is particularly characteristic of the paraglider aircraft which has the traditional parachute as it's ancestor. However, the parachute differs in a number of ways. For example, only rarely does the parachute permit ascending; indeed, it is designed specifically to descend.
The suspensory area of the paraglider has become more specialized as the paraglider has evolved from the parachute. It's component parts are more akin structurally to the sport of parachuting or sky diving than to hang gliding or motorized aircraft. A complete paraglider aircraft can still be wrapped up into a flexible trash can sized bag weighing about 29 pounds. The concept of such a soft flexible aircraft is diametrically opposite to the concepts of rigid flying machines, such as the hang glider. It would seem that experts in the field are not able to conceptualize the possibility of any staging/framework/leverage platform for a paraglider. The paraglider expert only conceptualizes the rigid structure of the seat board (115) as a place for the pilot to sit.
The typical paraglider pilot might view the beauty and uniqueness of the paraglider as destroyed and transformed into something completely different by such machines as U.S. Pat. No. 4,934,630 (1990) whereby a motorized propeller is attached to the back of the paraglider harness.
The control bar (46) in invention, U.S. Pat. No. 5,160,100 (1992), is not relevant to non-motorized paragliders because the results of its use depend specifically on the powerful motor and propeller system. Please see the discussion of this point in the patent in column 2, lines 5-22. This removes the disclosure from the realm of the paraglider and hang glider art. The control bar adds no more specific function for the hands than the presently known hang glider and paraglider. The control bar in U.S. Pat. No. 5,160,100 has at least one feature that renders it incompatible with the configuration found on the typical paraglider and hang glider; namely, the pilot is suspended from the control bar.
2.B. PRESENT PARAGLIDER CONTROLS
Both the hang glider and paraglider include some basic means to affect direction of movement, angle of attack and configuration of the wing. The basic hang glider and paraglider use quite crude methods. For example, the hang glider involves a primitive whole body weight shifting by hands holding on a control bar.
The paraglider pilot often uses lateral weight shifts through his buttocks on the seat board. More pilot weight on one side and less on the opposite causes the paraglider gradually to roll and then yaw a bit effecting a slight slow turn.
However, in accordance with invention U.S. Pat. No. 5,029,777 (1991), the pilot may also effect pitch changes with a weight shift in his seat from front to back. In turbulent winds, especially found in thermal conditions for soaring, pilots find such multi-directional seat motility dangerous and unsettling.
As in FIG. 1, the paraglider pilot is instructed to use each hand to hold a cloth brake loop (120) attached to brake lines (121) which are attached to the wing trailing edge (102) of the canopy wing (100). Holding down both brake loops (120), with the hands, at a level about 4 inches below the top of the pilot's shoulder is recommended to prevent wing deflation/collapses. This position is shown in FIGS. 2 and 3 as a dotted line (148).
Pulling just one brake loop (120) will turn the aircraft in the direction of the hand that is pulling. Letting up on the brake loops (120) allows the trailing edge (102) of the wing (100) to rise and the whole outline of the airfoil wing (100) is flattened; thus, the paraglider will fly faster.
Related art allows only one way to position the vital brake loop (120), other than being actively held by the hand. This one position occurs when the pilot releases the brake loop (120) and the brake loop (120) is pulled up by the flying wing (100) to a brake loop movement limiter (122) located on the D riser strap (107d) above the head as shown in FIGS. 1 and 2. In related art, the brake loop limiter (122) is a ring or other guide through which the brake line (121) passes. Without this brake loop limiter (122), the brake loop (120) would be blown out of reach of the pilot during reverse launch or while in the air. The brake loop limiter (122) has no other function; thus, it plays no part in keeping the wing (100) inflated or modifying the shape of the paraglider wing (100). On the ground, most paragliders have a holding means, often a button snap in means, to anchor temporarily the brake loop (120) on the D riser (107d), near brake loop limiter (122).
German Patent No. 4,101,241 (1992) describes a slightly different way of attaching the brake line (121) to the wing (100), but otherwise shows the identical approach of a hand held loop with its line passing through a similar posterior riser strap limiter, like the above mentioned brake loop limiter (122).
Besides the changes induced by altering the position of the constantly used brake loops (120), the pilot can effect additional changes in the wing (100) by pulling with his bare hands at one or more straps (107a-d) or wing suspension lines (106); namely, B riser stall, D riser stall, and wing tip collapse. An additional add on element is a trim tab system (149) in the D riser (107d) area.
Nothing involves the legs, except an add on speed stirrup system (130 through 136), to modify the paraglider in flight.
Thus, for flight purposes there are four control methods for the hands, one for the legs, and one for the buttocks.
2.C. THE SPEED STIRRUP SYSTEM
A pilot may choose to add on a speed stirrup system (150) to the basic paraglider. This system is not known to be patented, but is in public use as illustrated in FIGS. 1 and 2, at (130-132) and FIG. 3 at (131, 135, 136).
FIG. 2 and 3 shows the speed stirrup (130) as a rigid tube structure. An example, is a plastic tube of 10 inches by 3/4 inches overall diameter with walls about 3/32 inches thick. It usually dangles by speed stirrup cords (131) which are below either side of the seat board (115) area. The pilot's feet can push at the speed stirrup (130), which is part of the total speed stirrup system (150). This system enables the pilot's feet to effect about 4 inches of shortening on the A riser (107a). It does so by the particular attachments which allow the leg to pull on cord (131) which goes through a speed stirrup pulley (135) attached to the A riser (107a) about 4 inches above the final attachment point (136) of cord (131) on the A riser (107a). Thus, pushing on speed stirrup (130) causes the speed stirrup attachment (136) to be pulled to the speed stirrup pulley (135) attachment, thus shortening the A riser (107a) by about 4 inches. This also produces a much lesser shortening of riser B (107b) and riser C (107c). Therefore, pushing at the speed stirrup (130) will flatten the wing (100) by more complex changes to the wing than is done by the flattened wing shape resulting from having no downward force on the brake loops (120) from the pilot's hands. The practical effect of pressure on the speed stirrup (130) is to cause the paraglider to fly faster.
Among limitations and disadvantages of this system is that the pilot has to keep exerting pressure on the speed stirrup (130) to keep the faster speed. This is tiring and prevents more use of the weight shifting in one's seat board (115) to achieve flatter turns with less loss of altitude. In addition, one can not fix the speed system in the fastest configuration so that one can launch in faster winds. Also, it is much more difficult to get the paraglider certified as stable when changes to more than one pair of risers is held in place by some sort of fixing system that requires no muscle power. Finally, the maximum the legs can move is about 10 inches. This larger movement is possible where there is a 2 pulley arrangement in speed stirrup pulley (135) area.
Current art discloses no assembly whereby the pilot's legs may be used for any other function during flight than pushing at the speed stirrup (130) to cause the paraglider to fly faster. Of course, however, at ground level, the legs are used to launch the aircraft by running and the legs are used to land.
Another problem with the current speed stirrup system is that it is often difficult for the pilot to hook the speed stirrup (130) with a foot, especially in turbulent winds, or when the pilot is anxious because of a risky situation that has developed. Some pilots have used a solution to the unhookable stirrup problem that adopts a stretchable stirrup to speed stirrup foot cord (132) as illustrated in FIG. 2. Before launch, the pilot loops one end of the speed stirrup foot cord (132) around his shoe. The other end of the speed stirrup foot cord (132) is attached to the rigid speed stirrup (130). When the pilot straightens his leg, speed stirrup foot cord (132) brings the speed stirrup (130) into a position whereby the pilot can try to snag speed stirrup (130) with the other shoe.
However, this solution has its own problem because it increases the flailing of the dangling stirrup against the legs during the run and related twisting maneuvers on take off. This is annoying and disconcerting, especially in difficult take off and landing conditions, because the pilot may be tripped by the flailing stirrup. The cord also makes for slight jerking of the entire pulley/cord system, through the loop/stirrup set up, which destabilizes the wing. In addition, the pilot often does not have the luxury of landing on golf-course-smooth turf. All of the dangling cords may very easily become entangled in bushes and weeds.
Another method in current use adopts a tough but flexible speed stirrup cord tube (133), typically coming down another 12 inches below the speed stirrup (130), FIG. 2A. Speed stirrup cord tube (133) makes it easier for the pilot to find with the foot. The speed stirrup cord (131) in this case does not pass horizontally through speed stirrup (130), but through additional vertical holes in speed stirrup (130) then through speed stirrup cord tube (133).
2.D TRIM TAB SYSTEM
A few paraglider models can be certified with trim tabs, FIG. 3. These use 2 synthetic straps (141, 145), about 15/16 inches wide and 1/16 inches thick on each of the left and right D risers (107d). These straps are part of the entire trim tab system (149). A trim tab strap (141), one on the right and one on the left, is attached on each D riser (107d) as shown at trim tab straps (141) in FIG. 3, 4, 17. Typically, each trim tab strap (141) is looped around one end of trim tab law buckle (144), FIG. 17. Each trim tab buckle strap (145) has one end attached to the D riser (107d) and it's other end passes through the trim tab jaw clamp (142), which has a spring clamp built inside.
Changing the trim tab straps (141) can only be done by searching them out, trying to grab trim tab straps (141), then moving the trim tab straps (141) by pulling down with the hands on the ends that pass through the trim tab jaw clamp (142). The maximum that can be pulled down is 4 inches and this shortens the D riser along with some shortening of risers C and B. After the trim tab strap (141) length has been changed, it is immediately held in place automatically by the spring clamp part of the trim tab jaw clamp (142). The pilot can then return full attention to the brake loops (120).
To return the D riser (107d) to its full length, the pilot searches for the trim tab jaw clamp (142), tries to pinch the spring clamp, then continually pinches over a period of time of more than one second the spring clamp with the fingers to keep open the spring clamp to allow the upward pressure of the wing (100) to pull the trim tab strap (141) completely back up through the trim tab jaw clamp (142). This in turn allows the back part of the wing (100) to lift; therefore, a flatter shape and ability to fly faster. This use of the hands to operate the trim tab system prevents the use of the hands in attending only to keeping the brake loops (120) in the optimum position for safety.
Another disadvantage of the present trim tab jaw clamp (142) is that one side actually hangs pressed against another riser, so it is not easily and quickly possible to insert the fingers into position to be able to fully squeeze the spring clamp. Also, different than a plain cam buckle, the fingers must be kept on the spring clamp to prevent the built in spring from closing the spring clamp, thus preventing any more movement of the trim tab strap upward. This situation means that longer time away from attending to the brake loops (120) is required thus increasing risk.
Oversimplifying, the trim tab system's lower trim tab buckle straps (145) in effect permit about the same effect as the use of the speed stirrup (130); namely, inducing a faster or slower flying wing configuration. The trim tab system, however, omits any use of the legs, among other differences. In addition, the trim tab jaw clamp (142) allows the trim tab strap (141) to be fixed at the changed length while the hands return to managing the brakes. FIG. 4 indicates about where the speed stirrup system (150) and trim tab system (149) pull on primarily the A risers (107a) or D risers (107d) respectively. Seldom does a pilot get both speed stirrup and trim tab systems on his glider. It is not known if a paraglider has ever been safety rated using both.
Given the dependence of these ultralights on fickle winds, it is important to put safety above such performance issues as maximum lift, glide ratio and speed.
The pilot is much safer when he can attend as much as possible to maintaining optimum pressure on and positioning of the brake loop (120). The pilot should be ready to change brake loop (120) position at a moment's notice. The pilot is also much safer if he maintains his eyes in the direction of his desired flight path and/or looking out for other air traffic which is frequently heavy.
No mechanism currently exists for accomplishing at least three maneuvers without risking poor positioning of the brake loops (120) that significantly introduces risk, especially in strong or turbulent wind conditions. Such wind conditions can occur unpredictably.
Not infrequently the entire paraglider and the pilot are being bounced by wind gusts. The performance of three maneuvers in dangerous conditions is always more difficult than practicing the above steps in smooth conditions.
The three maneuvers risk undesired wing collapse because performing these takes the locations of the brake loops (120) away from the optimum stabilization point (148), about 4 inches below the top of the shoulder. The three maneuvers include: Wing Tip Collapse, B Riser Stall, and Trim Tab Adjustment already discussed. These three maneuvers cause double jeopardy because they also require removal of the eyes from focusing on the above mentioned safety concerns. Current yearly paragliding mishap reports reflect one of the most frequently mentioned problems is wing collapses or stalls. Collapses and stalls are more likely when the pilot fails to provide the correct amounts of brake pressure.
2.E WING TIP COLLAPSE AND B RISER STALL
To descend quickly and lose forward speed, the pilot grasps the carabiner quicklink (109) of the B riser (107b), pulls down 15-20 inches, and holds it down. This produces B riser stall and loss of most of the wing's lifting capacity.
Referring to FIGS. 3, 4, and 6, to fly as fast, yet descend more quickly, the pilot has to perform the following steps to modify the wing, i.e., a 20% wing tip collapse on each side known as Big Ears. First the pilot has to take his eyes off the best focal points in order to try and locate just 4 wing suspension lines (106) among 40 that are 10-15 inches above his head. He has to stretch up both hands as far as they can reach to grab just the 2 outer wing suspension lines on each A riser (107a) about 6 inches above the carabiner quicklink (109). Then he has to pull these lines laterally, then downward about 12 inches and hold them down. All this time the pilot has to ignore the proper positioning of the critical brake loops (120). Trying to pull straight down on said wing suspension lines (106) too close to the carabiner quicklink (109) is futile because this does not allow enough leverage to overcome the lift of the wing unless a pilot is remarkably strong. Even then, directly pulling down risks pulling down all 5 wing suspension lines (106) attached to the carabiner quicklink (109) of A riser (107a).
Having to reach up at least as high as the carabiner quicklink (109) of the A riser (107a) is awkward and only minimally allows holding the outer 2 wing suspension lines (106) of A risers (107a) in conjunction with holding onto the brake loops (120). Being able to do so quickly and easily would help with spot landing. Sometimes a wind gust blows the paraglider up from the path to a desired landing spot. If the pilot had a device that would help him hold and make small modifications in both of the 2 outer A riser (107a) wing suspension lines (106) and at the same time with the brake loops (120), he could better reduce the effect of unwanted lift and/or lower his altitude if he found himself coming in too high for the landing spot he needed.
To summarize, the current art paraglider parts of critical focus for control which the pilot must find, are: the brake loop (120), the first 5-10 inches of the 2 outer wing suspension lines (106) of the A riser (107a), the very top of the B riser (107b), the lower trim tab strap (141), the trim tab jaw clamp (142) and perhaps others.
2.F. VISUAL SUPPORT FOR CONTROLS
There is an absence of visual clues, color and patterns, to facilitate the finding of critical parts of the paraglider control system. Currently there is only a multitude of confusing colors often drawing attention to parts of the paraglider of no flight value. For example, bright yellow main horizontal harness straps (114) are often used.
2.G. OTHER CURRENT ART CONSIDERATIONS
Despite the need for the pilot to perform many flight functions at the same time, the workable and presently used hang gliders and paragliders do not allow the pilot to take advantage of the unique capacities of the fingers of the hand nor allow a direct working relationship between the fingers and the power of the legs to control the paraglider. In present paraglider systems the pilot has only a featureless tube speed stirrup (130) for the legs to act directly on the risers or featureless cloth brake loops (120) for the hands to directly act on the wing (100).
When having to deal with the brake loop (120)/brake line (121), any wing suspension lines (106) or one of the 4 pairs of risers (107), such as the two A risers (107a), current art paragliders have no contrivance to allow these parts to be lowered, held down, and released in one second. Of course, the pilot can actively hold these parts. Nor does current art allow at least retaining both brake loops about 4 inches below the top of the shoulder, positioned at the maximum stabilization position (148), whenever the hands are needed elsewhere.
There is another deficiency in current art. With current art at times the lifting air is so strong at take off that it is impossible for the pilot to make a safe launch. This is because he does not have time to pull the wing off the ground into the air and check the wing for proper inflation then position himself before the air lifts him dramatically off the ground. No current device allows the pilot to make a temporary large reduction in the lifting power of the wing until the pilot has time to assure safe integrity of the paraglider. Such a device must also allow quick and easy reestablishment of the lifting power for take off and rapidly penetrating forward.
Current art does not make use of any hook like device as part of a combination for holding down parts of the wing or for attaching parts together.
No current art has the elements of the present invention, i.e., a master control system for a number of control functions to be controlled while the hands are used to keep properly positioning the brake loops. Nor do present implementations have clutch, gear shift or transmission box equivalent apparatuses.
Another disadvantage is the current art paraglider pulley system. In a pulley system if a cord is not taught nothing will be effectuated until the cord is pulled straight and taught or until the pressure against an object against which the cord will straighten is greater than the weight of the object at the end of the cord. Also the cord will scrape across anything it touches. Current art does not use pull-pull cable systems to alleviate such problems.
2.H. SUMMARY OF MECHANICAL IMPLEMENTATIONS IN PARAGLIDERS
Thus, mechanical inventions in the field of what is usually conceptualized as an aircraft are not obvious to those involved in the art of hang gliding and paragliding to be applicable to paragliding and hang gliding. Simple machines include: the lever, pulley, wheel, axle, screw, and inclined plane/wedge in order to transmit or modify force or motion. The basic, without add ons, paraglider makes minimum use of simple machines for flight controls. For examples, the quicklinks make use of screw pairs sometimes with a spring added. Some of the harness buckles (116) have lever like elements.
A pilot can however add on the speed stirrup or trim tab system to a basic paraglider. The speed stirrup system makes use of the pulley machine. The most elaborate mechanical device as part of any paraglider is probably the trim tab jaw clamp (142) of the trim tab system. This clamp has a rod and a lever to open a spring in its housing, FIG. 17.
One definition of a machine is an apparatus with inter-related parts to perform work. Very broadly speaking, perhaps the wing is a machine of panels of cloth that converts the forces of the air to the work of moving the pilot.
Nor is there any use of more than two transmission elements in one device that exists in the paraglider assemblage. One definition of transmission elements includes elements for the transmitting of motive force. Such elements include: shafts, gears, belt trains, couplings, linkages, clutches, brakes, power screws, cams, flywheels, chain drives and bearings. Again, the brake line (121) runs from human arm power which is applied on the brake loop (120) to effectuate desirable changes, work, in the trailing edge (120) of the wing (100); therefor, maybe line (121) is a transmission element.
Current art does not contain transmissions with clutches. Typically, there is a shift device along with a clutch. In paragliders there is no shift device equivalent. A shift equivalent facilitates the positioning of one part in relation with a second part so as to enable the apparatus to perform more than one output of or internal change within the apparatus.
If paragliders had shift devices such devices would allow many novel actions including allowing the pilots legs and hands to form a combination such as one would find in a bicycle's manual clutch/gear shift transmission power train/linkage system.
The instant invention makes application to paragliders of pull-pull/pull-push cable systems. pull-pull and pull-push cables have a stiff outer sheath/conduit that does not move during functioning. There is an inner wire core (51a) freely movable inside the sheath. When properly installed these cables allow the user to pull something to or push something away from one end of the sheath from a point at the opposite end of the sheath. The two sheath ends may be six or more feet apart. These cables do not exert pressure on or scrape against anything outside the sheath between ends of the sheath. The control end can move freely about one end of the sheath and it can still effect the desired movement at the opposite end of the outer sheath. A common example is the cable system on bicycles.